A £10.46million move has appeared on the cards for several weeks now, and the 21-year-old told Bild magazine it will be wrapped up in the coming days.
"I am going to sign on (for City) before leaving for the World Cup and the deal will be completed," he said.
"It has been decided that I am moving there."
Boateng confirmed City manager Roberto Mancini had visited him in Hamburg and talked him into the move.
"He came with two representatives to Hamburg and we chatted for one or two hours," said Boateng.
"He convinced me to make the transfer. He believes that I will definitely need a few months to get settled in once in England, but that he sees so much potential in me that he will improve me.
"Even if many people say that I am going to struggle to make the breakthrough, I am confident that I will.
"I am not afraid of anybody."
Boateng is keen to leave Germany, where he says his family is being hounded by the media after his half-brother Kevin-Prince's foul on Michael Ballack in the FA Cup final ruled the Germany captain out of the World Cup.
Jerome could come up against his sibling in Germany's final group game against Ghana since Kevin-Prince recently switched allegiances, which was permissible due to a parental link with the African nation.
That game is already taking on a new significance due to Kevin-Prince's tackle on the Chelsea midfielder, but Boateng does not like the way the media have been shadowing his family members wherever they go.
"It disturbs me the way our family name is being dragged around in public and my family is not being left in peace," he said.
"It is not on that my big brother George suddenly has cameras on his doorstep and he is being forced to stay indoors.
"This has overstepped the mark. It has been ridiculous."
Boateng has been on international duty with Germany in their training camps in Sicilia and Sudtirol and will only get to spend a few days at home from Friday before jetting out to South Africa, but the reports he has received each time he has called home have disturbed him.
He even called the police to ask them to remove photographers and reporters from his family home, but the answer he received shocked him even further.
"They said I have just got to live with that, being a Boateng," he reported.
"That has gone too far. That is not on. What is the world coming to when my family cannot go out for a coffee or my brother cannot play with his children in the garden peacefully?"